[1]} propose to add a user-side fairness criterion to the trade-off above, to ensure that worse-off users do not bear the cost of reducing exposure inequalities among items. Their evaluation involves multi-dimensional trade-offs between specific points of the generalized Lorenz curve. Using the formulation (REF ) of GGFs, trade-offs between maximizing the cumulative utility at a specific quantile \(q\)  of users and total utility can be formulated using a parameter \(\omega \in [0,1]\)  as follows:
\(g^{\rm user}({u}) = \sum _{i=1}^n {w}_i^{\prime } {U}_i \quad \text{with~} {w}_{\lfloor qn\rfloor }^{\prime }=\omega \text{~and~} {w}_n^{\prime }=1-\omega ,\) 
